FIELD OF THE INVENTION
The present invention relates to an apparatus for automatically detecting the occurrence of a defective or broken cable and for automatically switching the data transmission from the broken cable to another cable and a method therefor. Particularly, the present invention relates to an apparatus and a method, in which, when a defect or breakage is discovered in a multi-core cable during data transmission or receiving, the defect is displayed, and an extra cable in reserve is automatically switched into use, so that the data transmission or receiving can be continued.